This invention is an improvement over U.S. Pat. No. 3,903,810. Vehicles of the general type involved herein are known. For example, see U.S. Pat. No. 3,356,040. As disclosed in said patents, a vehicle is guided for movement along the track and has a speed control wheel angularly adjustable with respect to a longitudinally extending drive shaft. The relative rotative position of said wheel with respect to said drive shaft controls the speed of movement of the vehicle along the tracks.
In U.S. Pat. No. 3,903,810, the control member is supported by a spring biased latch when disposed in its operative position. This invention simplifies the number of components involved by eliminating the latch and causes the function of the latch to be performed by the cam follower on the vehicle.